camera.attachControl(canvas);
camera.setTarget(new BABYLON.Vector3(0, 0, 0));

scene.addLight(light);
scene.addMesh(arm_left1_joint);
scene.addMesh(arm_right1_joint);
scene.addMesh(arm_left2_joint);
scene.addMesh(arm_right2_joint);
scene.addMesh(arm_left1);
scene.addMesh(arm_right1);
scene.addMesh(arm_left2);
scene.addMesh(arm_right2);
